Biomedical scientist Cunrui Huang takes a closer look at hand drying

This article was taken from the May 2013 issue of
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Hot-air
dryers A standard hand-dryer takes 30 seconds longer than a towel.
This time difference is important: wet hands support and transmit
more bacteria. "But rubbing hands while under hot-air dryers leads
to greater bacterial numbers and airborne dissemination," Huang
warns. "It might be that rubbing hands causes bacteria to migrate
from hair follicles to the skin surface."

Jet-air
dryers Jet-style dryers are fast: ten seconds of being blasted
with one is more effective than 30 seconds under a conventional
dryer. But they lead to greater contamination of the toilet, as
they can disperse bacteria further. And they're noisy: "In
washrooms with jet air dryers, the noise level could constitute a
potential risk to those exposed to it for long periods," says
Huang.

Paper towels The clear winners when it comes to hygienic hand-drying,
paper towels attain a dryness of 99 per cent after 15 seconds'
drying time, or 90 per cent after ten seconds, according to two of
the studies reviewed. Paper towels are also easy to recycle. "Hand
hygiene adherence would possibly decrease if paper towels are not
available in washrooms." summarisies Huang.